ENVIRONMENT-FRIENDLY CHROMIUM-FREE COATING COMPOSITION FOR A ZINC-COATED STEEL SHEET CAPABLE OF APPLYING TO AN EXISTING FACILITY AS A POST-PROCESSING SOLUTION

摘要

PURPOSE: An environment-friendly chromium-free coating composition for a zinc-coated steel sheet is provided to form a chromate coating of a chromium-free conversion type.;CONSTITUTION: An environment-friendly chromium-free coating composition contains 2~5 grams per liter of titan ion, 20~40 grams per liter of phosphate ion, 5~10 grams per liter of calcium ion, 5~10 grams per liter of nitrate ion, 5~10 grams per liter of silicon ion, and 5~10 grams per liter of polyvinyl alcohol. The environment-friendly chromium-free coating composition for a zinc-coated steel sheet can be used at a spray coating process and a roll coating process at the same time.;COPYRIGHT KIPO 2010